<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>bootstrap</title>
    <link rel="stylesheet" href="css/bootstrap.min.css">
    
</head>
<body>
    <div class="dropdown">
        <button class="btn btn-info "  data-toggle="dropdown" >
          按钮
          <span class="caret"></span>
        </button>
        <ul class="dropdown-menu" ">
          <li><a href="#">Action</a></li>
          <li><a href="#">Another action</a></li>
          <li><a href="#">Something else here</a></li>
          <li role="separator" class="divider"></li>
          <li><a href="#">Separated link</a></li>
        </ul>
    </div>
    <div class="dropdown">
        <div data-toggle="dropdown">我是div</div>
        <ol class="dropdown-menu">
            <li>1</li>
            <li>2</li>
            <li>3</li>
            <li>4</li>
        </ol>
    </div>
    <div style="margin-top:200px"></div>
    <div class="dropup">
        <button class="btn btn-info "  data-toggle="dropdown" >
          按钮
          <span class="caret"></span>
        </button>
        <ul class="dropdown-menu" ">
          <li><a href="#">Action</a></li>
          <li><a href="#">Another action</a></li>
          <li class="disabled"><a href="#">Something else here</a></li>
          <li role="separator" class="divider"></li>
          <li><a href="#">Separated link</a></li>
        </ul>
    </div>

<script src="js/jquery-3.6.0.min.js"></script>
<script src="js/bootstrap.min.js"></script>
</body>
</html>